Magnetic recording heads have utility in a magnetic disc drive storage system. Most magnetic recording heads used in such systems today are “longitudinal” magnetic recording heads. An alternative to longitudinal recording is “perpendicular” magnetic recording. Perpendicular magnetic recording is believed to have the capability of extending recording densities well beyond the limits of longitudinal magnetic recording.
Perpendicular magnetic recording heads for use with a perpendicular magnetic storage medium may include a pair of magnetically coupled poles, including a main write pole having a relatively small bottom surface area and a flux return pole having a larger bottom surface area. A coil having a plurality of turns is located adjacent to the main write pole for inducing a magnetic field between that pole and a soft underlayer of the storage media. The soft underlayer is located below the hard magnetic recording layer of the storage media and enhances the amplitude of the field produced by the main pole. This allows the use of storage media with a higher coercive force, consequently, more stable bits can be stored in the media. In the recording process, an electrical current in the coil energizes the main pole, which produces a magnetic field. The image of this field is produced in the soft underlayer to enhance the field strength produced in the magnetic media. The flux density that diverges from the tip into the soft underlayer returns through the return flux pole. The return pole is located sufficiently far apart from the main write pole such that the material of the return pole does not affect the magnetic flux of the main write pole, which is directed vertically into the hard layer and the soft underlayer of the storage media. A magnetic recording system such as, for example, a perpendicular magnetic recording system may utilize a write pole having uniform magnetic properties, i.e. the write pole is formed of a single material having a uniform magnetic moment. However, it is well known that such a write pole can exhibit skew effects which can degrade adjacent tracks. In addition, it is well known that the skew effects also result in non-desirable side writing occurring during the writing operation.
Accordingly, there is identified a need for an improved recording head that overcomes limitations, disadvantages, and/or shortcomings of known recording heads.